<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>		
	<script>
		function changeTitle(){
			document.title = '网页标题';
		}
	</script>
</head>
<body>
	<input type="button" value="单击我,设置标题栏信息" onclick="changeTitle()">
</body>
</html>